Laser systems can perform non-contact machining and therefore are used in various fields such as a machining field and a medical field, and are demanded to provide higher outputs.
As one of methods which realize higher outputs of these laser systems, there is a method of combining laser lights output from a plurality of optical fibers by means of an optical fiber combiner and outputting the light from one optical fiber. Following Patent Document 1 discloses an optical fiber combiner which can be used for these laser systems.
In the optical fiber combiner disclosed in Patent Document 1, a plurality of optical fibers are inserted in penetration holes of capillaries having a plurality of penetration holes, and end portions of the capillaries are connected to a bridge fiber. This bridge fiber has a tapered portion an outer diameter of which is gradually reduced from a side on which the bridge fiber is connected with the capillaries to an opposite side, and an end surface on the side on which the outer diameter is reduced is connected to other optical fibers. According to this optical fiber combiner, lights emitted from respective optical fibers are combined by the bridge fiber and become lights of significant power. Further, the lights of significant power enter the optical fibers from the bridge fiber. Consequently, the lights of significant power can enter the other optical fibers, and output lights of significant power can be extracted from these other optical fibers.